关键词: 杂交水稻, 制种, 立体工厂化育秧, 秧苗素质, 生育期, 经济性状

Abstract:

This study used parents A8450, Yangtai A, and R128 as materials, to explore the impact of three-dimensional industrial seedling raising on the characteristics of parents in hybrid rice seed production. Three seedling-raising methods were set up:“W”-shaped three-dimensional circular industrial seedling tray raising, field seedling tray raising, and traditional wet bed seedling raising. Five seedling age treatments were designed under each method. The differences in seedling quality, growth characteristics, maximum seedling number, and spike-grain structure among different treatments were systematically compared. The results showed that the overall seedling quality of“W”-shaped three-dimensional circular industrial seedling raising was relatively poor. The leaf emergence rate slowed down after 14 days of seedling age. By 26 days of seedling age, the leaf age did not exceed 2.6 leaves, the seedling height was lower than 20 cm, the basal stem width was less than 2.6 mm, and the plants were relatively weak. In contrast, the seedling quality of field seedling tray raising and traditional wet bed seedling raising was good during the same period. After transplanting to the field, the differences in characteristics among different treatments narrowed. The variation range of the number of main stem leaves was within 0.6 leaves, and there were no significant differences in the number of effective panicles per hill, maximum seedling number, panicle length, and total grains per panicle. Industrial seedling raising had a significant impact on the duration from sowing to heading of the parents, with the order being“W”-shaped three-dimensional circular industrial seedling raising≥field seedling tray raising≥traditional wet bed seedling raising. Moreover, as the seedling age extended, the duration from sowing to heading of the industrial seedling raising treatment increased to a greater extent. In addition, the total grains per hill of“W”-shaped three-dimensional circular industrial seedling raising were 1.48%-9.82% lower than those of field seedling tray raising and 8.41%-19.85% lower than those of traditional wet bed seedling raising. In conclusion,“W”-shaped three-dimensional circular industrial seedling raising can be used for seedling cultivation of parents in hybrid rice seed production, especially helping to alleviate problems such as seedling rot, low seedling survival rate, and poor uniformity that are prone to occur in field mechanical transplanting seedling raising under low-temperature conditions. However, attention should be paid to the impact of its extended duration from sowing to heading during application. The sowing and transplanting dates should be adjusted in a timely manner, and cultivation measures should be taken to increase the total grains per hill. The results of this study can provide technical basis and scientific reference for the promotion and application of three-dimensional industrial seedling raising technology in hybrid rice seed production.

Key words: hybrid rice, seed production, three-dimensional factory seedling raising, seedling quality, growth period, economic traits